Botulinus toxin is a proteinous exotoxin produced by Clostridium botulinum and acts on the peripheral nervous system. When ingested by human, the botulinus toxin gives rise to intoxication called botulism which is accompanied by paralytic symptoms. It is well known that the neurotoxin is absorbed from the alimentary tract and acts peripherally at the neuromuscular junctions controlled by the parasympathetic nerves. The toxin thus interferes with the release of acetylcholine from the chlorinergic motor nerve endings and causes botulism. In respect of the mode of action of the botulinus toxin, it has been widely accepted that a certain acidic glycolipid, viz., the ganglioside GT1b present in the neuromembrane acts as a receptor for the toxin. While other gangliosides such as the gangliosides GQ1b and GD1b also have the ability of combining with botulinus toxin, such an ability of these gangliosides is inferior to that of the ganglioside GT1b and, for this reason, it has been considered that the gangliosides GQ1b and GD1b are less responsible for the action to the botulinus toxin.
The treatment of botulism is extremely difficult and, at the present time, there is practically no other method of treatment than to cease the symptoms. It may be presumed that botulism could be treated with use of the ganglioside GTb1 as an antagonist to the botulinus toxin, in view of the mode of action of the toxin as above discussed. The ganglioside GTb1, which thus acts as an antagonistic receptor for the botulinus toxin, will combine with the toxin and will prevent the onset of the toxicity thereof. A problem is however encountered in that the source presently available of the ganglioside GTb1 is none but the bovine brain, which is so expensive that the method of treating botulism with use of such a ganglioside has seldom been put into practice.
Under these circumstances, it is an object of the present invention to provide an economical botulinus toxin neutralizer which can be used as an antagonistic toxin receptor for the treatment of botulism and which will thus facilitate the prevention and treatment of botulism.
It is another object of the present invention to provide a method of preparing such a botulinus toxin neutralizer.